Rfc2898DeriveBytes 类
定义
重要
一些信息与预发行产品相关，相应产品在发行之前可能会进行重大修改。 对于此处提供的信息，Microsoft 不作任何明示或暗示的担保。
通过使用基于 HMACSHA1 的伪随机数生成器，实现基于密码的密钥派生功能 (PBKDF2)。
public ref class Rfc2898DeriveBytes : System::Security::Cryptography::DeriveBytes[System.Runtime.Versioning.UnsupportedOSPlatform("browser")]
public class Rfc2898DeriveBytes : System.Security.Cryptography.DeriveBytespublic class Rfc2898DeriveBytes : System.Security.Cryptography.DeriveBytes[System.Runtime.InteropServices.ComVisible(true)]
public class Rfc2898DeriveBytes : System.Security.Cryptography.DeriveBytes[<System.Runtime.Versioning.UnsupportedOSPlatform("browser")>]
type Rfc2898DeriveBytes = class
inherit DeriveBytestype Rfc2898DeriveBytes = class
inherit DeriveBytes[<System.Runtime.InteropServices.ComVisible(true)>]
type Rfc2898DeriveBytes = class
inherit DeriveBytesPublic Class Rfc2898DeriveBytes
Inherits DeriveBytes- 继承
- 属性
示例
下面的代码示例使用 Rfc2898DeriveBytes 该类为 Aes 类创建两个相同的键。 然后，它使用密钥对某些数据进行加密和解密。
using namespace System;
using namespace System::IO;
using namespace System::Text;
using namespace System::Security::Cryptography;
// Generate a key k1 with password pwd1 and salt salt1.
// Generate a key k2 with password pwd1 and salt salt1.
// Encrypt data1 with key k1 using symmetric encryption, creating edata1.
// Decrypt edata1 with key k2 using symmetric decryption, creating data2.
// data2 should equal data1.
int main()
{
array<String^>^passwordargs = Environment::GetCommandLineArgs();
String^ usageText = "Usage: RFC2898 <password>\nYou must specify the password for encryption.\n";
//If no file name is specified, write usage text.
if ( passwordargs->Length == 1 )
{
Console::WriteLine( usageText );
}
else
{
String^ pwd1 = passwordargs[ 1 ];
array<Byte>^salt1 = gcnew array<Byte>(8);
RNGCryptoServiceProvider ^ rngCsp = gcnew RNGCryptoServiceProvider();
rngCsp->GetBytes(salt1);
//data1 can be a string or contents of a file.
String^ data1 = "Some test data";
//The default iteration count is 1000 so the two methods use the same iteration count.
int myIterations = 1000;
try
{
Rfc2898DeriveBytes ^ k1 = gcnew Rfc2898DeriveBytes( pwd1,salt1,myIterations );
Rfc2898DeriveBytes ^ k2 = gcnew Rfc2898DeriveBytes( pwd1,salt1 );
// Encrypt the data.
Aes^ encAlg = Aes::Create();
encAlg->Key = k1->GetBytes( 16 );
MemoryStream^ encryptionStream = gcnew MemoryStream;
CryptoStream^ encrypt = gcnew CryptoStream( encryptionStream,encAlg->CreateEncryptor(),CryptoStreamMode::Write );
array<Byte>^utfD1 = (gcnew System::Text::UTF8Encoding( false ))->GetBytes( data1 );
encrypt->Write( utfD1, 0, utfD1->Length );
encrypt->FlushFinalBlock();
encrypt->Close();
array<Byte>^edata1 = encryptionStream->ToArray();
k1->Reset();
// Try to decrypt, thus showing it can be round-tripped.
Aes^ decAlg = Aes::Create();
decAlg->Key = k2->GetBytes( 16 );
decAlg->IV = encAlg->IV;
MemoryStream^ decryptionStreamBacking = gcnew MemoryStream;
CryptoStream^ decrypt = gcnew CryptoStream( decryptionStreamBacking,decAlg->CreateDecryptor(),CryptoStreamMode::Write );
decrypt->Write( edata1, 0, edata1->Length );
decrypt->Flush();
decrypt->Close();
k2->Reset();
String^ data2 = (gcnew UTF8Encoding( false ))->GetString( decryptionStreamBacking->ToArray() );
if ( !data1->Equals( data2 ) )
{
Console::WriteLine( "Error: The two values are not equal." );
}
else
{
Console::WriteLine( "The two values are equal." );
Console::WriteLine( "k1 iterations: {0}", k1->IterationCount );
Console::WriteLine( "k2 iterations: {0}", k2->IterationCount );
}
}
catch ( Exception^ e )
{
Console::WriteLine( "Error: ", e );
}
}
}
using System;
using System.IO;
using System.Text;
using System.Security.Cryptography;
public class rfc2898test
{
// Generate a key k1 with password pwd1 and salt salt1.
// Generate a key k2 with password pwd1 and salt salt1.
// Encrypt data1 with key k1 using symmetric encryption, creating edata1.
// Decrypt edata1 with key k2 using symmetric decryption, creating data2.
// data2 should equal data1.
private const string usageText = "Usage: RFC2898 <password>\nYou must specify the password for encryption.\n";
public static void Main(string[] passwordargs)
{
//If no file name is specified, write usage text.
if (passwordargs.Length == 0)
{
Console.WriteLine(usageText);
}
else
{
string pwd1 = passwordargs[0];
// Create a byte array to hold the random value.
byte[] salt1 = new byte[8];
using (RNGCryptoServiceProvider rngCsp = new
RNGCryptoServiceProvider())
{
// Fill the array with a random value.
rngCsp.GetBytes(salt1);
}
//data1 can be a string or contents of a file.
string data1 = "Some test data";
//The default iteration count is 1000 so the two methods use the same iteration count.
int myIterations = 1000;
try
{
Rfc2898DeriveBytes k1 = new Rfc2898DeriveBytes(pwd1, salt1,
myIterations);
Rfc2898DeriveBytes k2 = new Rfc2898DeriveBytes(pwd1, salt1);
// Encrypt the data.
Aes encAlg = Aes.Create();
encAlg.Key = k1.GetBytes(16);
MemoryStream encryptionStream = new MemoryStream();
CryptoStream encrypt = new CryptoStream(encryptionStream,
encAlg.CreateEncryptor(), CryptoStreamMode.Write);
byte[] utfD1 = new System.Text.UTF8Encoding(false).GetBytes(
data1);
encrypt.Write(utfD1, 0, utfD1.Length);
encrypt.FlushFinalBlock();
encrypt.Close();
byte[] edata1 = encryptionStream.ToArray();
k1.Reset();
// Try to decrypt, thus showing it can be round-tripped.
Aes decAlg = Aes.Create();
decAlg.Key = k2.GetBytes(16);
decAlg.IV = encAlg.IV;
MemoryStream decryptionStreamBacking = new MemoryStream();
CryptoStream decrypt = new CryptoStream(
decryptionStreamBacking, decAlg.CreateDecryptor(), CryptoStreamMode.Write);
decrypt.Write(edata1, 0, edata1.Length);
decrypt.Flush();
decrypt.Close();
k2.Reset();
string data2 = new UTF8Encoding(false).GetString(
decryptionStreamBacking.ToArray());
if (!data1.Equals(data2))
{
Console.WriteLine("Error: The two values are not equal.");
}
else
{
Console.WriteLine("The two values are equal.");
Console.WriteLine("k1 iterations: {0}", k1.IterationCount);
Console.WriteLine("k2 iterations: {0}", k2.IterationCount);
}
}
catch (Exception e)
{
Console.WriteLine("Error: {0}", e);
}
}
}
}
Imports System.IO
Imports System.Text
Imports System.Security.Cryptography
Public Class rfc2898test
' Generate a key k1 with password pwd1 and salt salt1.
' Generate a key k2 with password pwd1 and salt salt1.
' Encrypt data1 with key k1 using symmetric encryption, creating edata1.
' Decrypt edata1 with key k2 using symmetric decryption, creating data2.
' data2 should equal data1.
Private Const usageText As String = "Usage: RFC2898 <password>" + vbLf + "You must specify the password for encryption." + vbLf
Public Shared Sub Main(ByVal passwordargs() As String)
'If no file name is specified, write usage text.
If passwordargs.Length = 0 Then
Console.WriteLine(usageText)
Else
Dim pwd1 As String = passwordargs(0)
Dim salt1(8) As Byte
Using rngCsp As New RNGCryptoServiceProvider()
rngCsp.GetBytes(salt1)
End Using
'data1 can be a string or contents of a file.
Dim data1 As String = "Some test data"
'The default iteration count is 1000 so the two methods use the same iteration count.
Dim myIterations As Integer = 1000
Try
Dim k1 As New Rfc2898DeriveBytes(pwd1, salt1, myIterations)
Dim k2 As New Rfc2898DeriveBytes(pwd1, salt1)
' Encrypt the data.
Dim encAlg As Aes = Aes.Create()
encAlg.Key = k1.GetBytes(16)
Dim encryptionStream As New MemoryStream()
Dim encrypt As New CryptoStream(encryptionStream, encAlg.CreateEncryptor(), CryptoStreamMode.Write)
Dim utfD1 As Byte() = New System.Text.UTF8Encoding(False).GetBytes(data1)
encrypt.Write(utfD1, 0, utfD1.Length)
encrypt.FlushFinalBlock()
encrypt.Close()
Dim edata1 As Byte() = encryptionStream.ToArray()
k1.Reset()
' Try to decrypt, thus showing it can be round-tripped.
Dim decAlg As Aes = Aes.Create()
decAlg.Key = k2.GetBytes(16)
decAlg.IV = encAlg.IV
Dim decryptionStreamBacking As New MemoryStream()
Dim decrypt As New CryptoStream(decryptionStreamBacking, decAlg.CreateDecryptor(), CryptoStreamMode.Write)
decrypt.Write(edata1, 0, edata1.Length)
decrypt.Flush()
decrypt.Close()
k2.Reset()
Dim data2 As String = New UTF8Encoding(False).GetString(decryptionStreamBacking.ToArray())
If Not data1.Equals(data2) Then
Console.WriteLine("Error: The two values are not equal.")
Else
Console.WriteLine("The two values are equal.")
Console.WriteLine("k1 iterations: {0}", k1.IterationCount)
Console.WriteLine("k2 iterations: {0}", k2.IterationCount)
End If
Catch e As Exception
Console.WriteLine("Error: ", e)
End Try
End If
End Sub
End Class
注解
Rfc2898DeriveBytes 获取密码、盐和迭代计数，然后通过对方法的 GetBytes 调用生成密钥。
RFC 2898 包括用于从密码和盐创建密钥和初始化向量的 (IV) 的方法。 可以使用基于密码的密钥派生函数 PBKDF2 使用伪随机函数派生密钥，该函数允许生成几乎无限长度的密钥。 该 Rfc2898DeriveBytes 类可用于从基键和其他参数生成派生密钥。 在基于密码的密钥派生函数中，基键是密码，其他参数是盐值和迭代计数。
有关 PBKDF2 的详细信息，请参阅 RFC 2898，标题为“PKCS #5：Password-Based加密规范版本 2.0”。 有关完整详细信息，请参阅第 5.2 节“PBKDF2”。
重要
从不对源代码中的密码进行硬编码。 硬编码的密码可以通过使用 Ildasm.exe (IL 反汇编程序) 、十六进制编辑器或只是在文本编辑器（如 Notepad.exe）中打开程序集来检索。
构造函数
| Rfc2898DeriveBytes(Byte[], Byte[], Int32) |
已过时。
通过使用密码、salt 值和迭代次数派生密钥，初始化 Rfc2898DeriveBytes 类的新实例。 |
| Rfc2898DeriveBytes(Byte[], Byte[], Int32, HashAlgorithmName) |
初始化 Rfc2898DeriveBytes 类的新实例，该实例使用指定的密码、salt、迭代数和哈希算法名称来派生密钥。 |
| Rfc2898DeriveBytes(String, Byte[]) |
已过时。
通过使用密码和 salt 值派生密钥，初始化 Rfc2898DeriveBytes 类的新实例。 |
| Rfc2898DeriveBytes(String, Byte[], Int32) |
已过时。
通过使用密码、salt 值和迭代次数派生密钥，初始化 Rfc2898DeriveBytes 类的新实例。 |
| Rfc2898DeriveBytes(String, Byte[], Int32, HashAlgorithmName) |
初始化 Rfc2898DeriveBytes 类的新实例，该实例使用指定的密码、salt、迭代数和哈希算法名称来派生密钥。 |
| Rfc2898DeriveBytes(String, Int32) |
已过时。
通过使用密码和 salt 大小派生密钥，初始化 Rfc2898DeriveBytes 类的新实例。 |
| Rfc2898DeriveBytes(String, Int32, Int32) |
已过时。
通过使用密码、salt 值和迭代次数派生密钥，初始化 Rfc2898DeriveBytes 类的新实例。 |
| Rfc2898DeriveBytes(String, Int32, Int32, HashAlgorithmName) |
初始化 Rfc2898DeriveBytes 类的新实例，该实例使用指定的密码、salt 大小、迭代数和哈希算法名称来派生密钥。 |
属性
| HashAlgorithm |
获取用于字节派生的哈希算法。 |
| IterationCount |
获取或设置操作的迭代数。 |
| Salt |
获取或设置操作的密钥 salt 值。 |